Advancement
===========
Experience points are divided into two categories: Gift EP, which is 
used for purchasing gifts, and Skill EP, which is used for purchasing 
skills. A character gains a level upon completing a milestone. Upon 
gaining a level, the character gains 1 Gift EP and 1 Skill EP. These 
may be saved or spent immediately.

Skills start at -2 and become more expensive to purchase as levels 
become higher. In order to achieve the next rank, the cost is as 
follows:

- -1: 1 EP.
- 0: 1 EP.
- +1: 2 EP.
- +2: 4 EP.
- +3: 8 EP.

Instead of choosing a gift, a character may also spend Gift EP to raise 
their attributes. This cannot be used to exceed the racial maximum of 
that character. Likewise, a character may start with low attributes in 
exchange for Gift EP, which may not be used to exceed the racial minimum 
of that character. In order to achieve the next rank, the cost is as 
follows:

- -2: 3 EP.
- -1: 3 EP.
- 0: 3 EP.
- +1: 6 EP.
- +2: 12 EP.
- +3: 24 EP.

Reducing a stat below 0 rewards 3 EP for each rank below 0.
